ok guys...
My PC is on a college LAN which has configured a terminal as http proxy [ and obviously we can connect to the internet thru that proxy only...no bypassing..itz not a gateway]
ip 172.24.2.1
port 8080
in yahoo messenger and alll...all i did was just give the proxy IP...no username and password...and it works

but here when i try these things..
Hostname:172.24.2.1
port 8080 support both
protocol proxy
i get "firewall: connection rejected!!!"

i tried all sorts of commands...[/firewall on; /firewall -p 172.24.2.1 8080 ]
but its not working...i am not able to connect....

and ya..if at all i have to provide username and password...where from do i get these??? i mean the college has provided us with user accounts on its linux server box...like say swordfish@collegename.edu ....so shud i use this username and the password to my account in personal college...seems wierd....i am confused....please help

First of all, are you sure the proxy is meant to intercept all Internet traffic and not just HTTP traffic on port 80? You should at least make sure that you have to, before you try to use the proxy in all Internet software.

The problem with IRC seems to be that the proxy's blocking the most common port used for IRC, namely 6667. Try finding servers that listen on other ports - 6668-6669 and 7000 are some common ones, but the best is to find really rare ones, like 5239. Connecting to IRC on a weird port might make you connect through your proxy unnoticed.

Another problem could be that you're simply specifying the wrong kind of proxy. Proxies used for relaying web pages are usually HTTP proxies, while proxies used for IRC are usually SOCKS4 or SOCKS5, as far as I can remember. If you have it set to SOCKS4, try SOCKS5, and vice versa.